This invention relates to a dispersible granular substrate suitable for use as a carrier for chemical agents, as well as a method for producing a granular substrate. More particularly, this invention relates to a medium weight dispersible granular substrate.
Generally, granular substrates are utilized as carriers for active chemical agents, such as for example herbicides or other pesticides. The terms “pesticide” or “pesticides” are used herein in the broad sense that includes herbicides. The carriers, with the active chemical agents, are utilized to distribute the active agent over a broad area. The carriers are generally inert compounds that, upon application, break down over time.
Existing water soluble granular substrates are nutrient-based carriers, conventionally formed of ammonium sulfate. However, ammonium sulfate acts as a fertilizer, providing a growth response that may not be desired, and can burn turf if misapplied or applied at high rates as, for example, a mound treatment for ant control.
In addition, conventional granular substrates often have a tendency to break apart, thus creating handling and distribution problems. Granular substrates that resist attrition are preferred because they will not degrade and therefore maintain their particle size during handling. While resistance to attrition is important, in some applications it is preferable that the carrier compound breakdown or disintegrate upon exposure to water.